Univex Calibration, Flow, Period, Model 5100-02-ITCombustible Gas Sensor Module, Page

Model 5100-02-IT Combustible Gas Sensor Module

5. CALIBRATION

5.1CALIBRATION FREQUENCY

The manufacturer specifies that sensor modules must be calibrated every 180 days. Periodic functional tests are advisable for critical applications and hostile environments.

The sensor module microprocessor software includes high level self checking algorithms which provide continuous sensor diagnostic and self adjustment. Users may elect to increase calibration periods based on low drift experience during the first two calibration periods.

5.2CALIBRATION PREPARATION

Calibration of the sensor is accomplished by simple menu based steps and application of span gas.

NOTE

If an error is made during any stage of the calibration process, hold the magnet stick at the Switch 1 for 10 seconds. A scrolling display will indicate “Operate Mode” and the sensor module will exit the calibration activity and return to normal operating mode. The calibration procedure can then be restarted.

Calibration must be performed only when the area is known to be clear of combustible gas. If necessary, use a portable instrument to confirm that there is no background combustible gas.

For compliance with Factory Mutual (FM) Approvals, the Sierra Monitor Model 1200-26, 1250-01, 1256-01, 1260 - 02 and 1260-42 are the FM Approved calibration gas delivery devices. Use Model 5358-01 Calibration Adapter or Model 5360-00 Gas Delivery Fitting.

5.2.1 CALIBRATION GAS DELIVERY METHODS

Calibration gas can be delivered to the sensors via the following delivery devices: Model 5358-01: Calibration Adapter - use with portable calibrators. See Fig 5-1.

Model 5360-00: Calibration Gas Delivery fitting - permanently installed fitting which allows tubing to be run to a convenient delivery location.

5.2.2 CALIBRATION PROCEDURE

Table 5-1 shows the step by step process of the calibration procedure.

The procedures requires that the menu “keys” be activated using the magnet stick. Each key press steps through the process of setting the zero value for clean air and then setting the span value.

At each of these steps, apply calibration gas of the value corresponding to the setting accepted on the sensor module display.

5.2.3 SENSOR EXPOSURE TO GAS

Figure 5-1

Model 5358-01 Calibration Adapter

Calibration gas must be delivered to the sensor using the flow rate and duration listed in below:

Model	Gas	Flow	Period
5100-02-IT Combustible		100-300 cc/min	Until Stable (minimum 3 minutes.)

NOTE:

Following calibration, the module counts down for 300 seconds. During this time the module is updating its internal memory and it

is very important that its power not be interrupted

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